Magnetic resonance imaging is an image taking method by which nuclear spins in an examined subject placed in a static magnetic field are magnetically excited by a radio frequency (RF) pulse having a Larmor frequency thereof so as to generate an image from data of magnetic resonance signals generated due to the excitation. A magnetic resonance imaging apparatus includes a gradient coil provided on an inside of a static magnetic field magnet. Further, in the gradient coil, an X coil that generates a gradient magnetic field along the horizontal axis of a substantially circular cylinder (the horizontal axis is perpendicular to a long axis of the substantially circular cylinder), a Y coil that generates a gradient magnetic field along a vertical axis of the substantially circular cylinder, and a Z coil that generates a gradient magnetic field along the long axis of the substantially circular cylinder are laminated together.
In recent years, high-speed image taking processes such as an Echo Planar Imaging (EPI) process are becoming popular. When performing high-speed image taking processes, because an electric current having a high power duty is applied to the X coil, the X coil generates heat most easily. Also, conventionally, the X coil has been laminated in the innermost position closest to the space formed on the inside of the substantially circular cylinder, which is the space in which a subject is placed. Although the gradient coil is provided with a cooling pipe for causing a cooling medium such as water to circulate, if the X coil is not sufficiently cooled, the comfortability of the subject is degraded. In some situations, there is a possibility that the image taking process may need to be stopped in compliance with a standard defined by the International Electrotechnical Commission (IEC).